Water resources in California are in increasingly short supply due to our natural geography, climate and water usage levels. As Southern California population grew rapidly following World War II the demands for water began to exceed the natural supply and it became clear that we had to devise new ways to replenish the aquifer underlying our communities.

Thoughtful planning and engineering resulted in a State Water Project that now brings water from northern California to southern California.The San Gabriel Valley Municipal Water District operates under the laws of California with respect to how much water we are authorized to take each year from the State Water Project to replace water that has been pumped from the aquifer below our communities. We also are part of the San Gabriel Valley Watermaster, which each year determines what our communities can safely extract from the aquifer and how much replacement water is required to offset over-pumpage.

As replacement or “supplemental” water is ordered from the State Water Project, it is channeled through our pipeline and system of “turnouts” to the many Spreading Grounds operated and maintained by the Los Angeles County Department of Public Works. That water then becomes available to our member cities.

The San Gabriel Valley Municipal Water District provides reliable supplemental water for the communities of Alhambra, Azusa, Monterey Park and Sierra Madre in a cost-effective and environmentally responsible manner.

The Water District procures water from the state water project that is used to supplement ground water supplies in its four member cities.


The San Gabriel Valley Municipal Water District was formed in 1959 after winning approval from the voters of Alhambra, Azusa, Monterey Park, and Sierra Madre. In anticipation of its long-term water needs, the Water District entered into a contract with the State of California Department of Water Resources in 1962 for the delivery of 25,000 acre-feet of water per year from the State Water Project. In 1964, the contract was amended to allow for 28,800 acre-feet. Today the District is one of 29 State Water Contractors who obtain water from the vast State Water Project and who pay for retirement of the bond used to construct it, as well as its operation and maintenance.

In 1969, the Water District constructed the Devil Canyon-Azusa Pipeline to deliver water from the State Water Project to the Main San Gabriel Basin. Starting in 1975 and continuing today, the Water District has been importing water from Northern California for replenishment of the San Gabriel Basin. In 1981, an additional outlet was added to the pipeline at San Dimas Wash.

In 1985, the Water District installed a 1.05 megawatt hydroelectric power plant at the San Dimas turnout to generate electricity in conjunction with its supplemental water deliveries. In 1995, we completed an extension of the Devil Canyon-Azusa Pipeline from Azusa to the Los Angeles County Department of Public Works' San Gabriel Canyon Spreading Grounds. The extension provides us with greater flexibility in delivering water to the Main San Gabriel Basin and better serving member cities. In 1998, another outlet was constructed at Big Dalton Wash to utilize the LA County Department of Public Works’ Citrus Spreading Grounds.